1. Aspergillus galactomannan appeared in urine of rabbits infected with A. fumigatus. Radiolabeled galactomannan was largely excreted in urine (42%) or deposited in liver (20%) of unimmunized rabbits. 2. Cured cryptococcosis patients had long-lasting, specific, decreased antibody response to immunization with cryptococcal polysaccharide. 3. The in vitro susceptibility test best able to predict protection of infected mice found that 11.5-35% of Candida albicans from various medical centers were resistant to flucytosine.